DETROIT— Call ‘em what you will: SUV, AAV, SAV, SUT, UUV or ACC. America’s obsession with the open road and love affair with wheels has created a category of vehicles that can barely be categorized. But by all accounts, they’re still familiar to those of us who look under their tough-guy skins. Of the 30 production and concept vehicles unveiled at this year’s show, more than two-thirds of them were — in a word — trucks.

But, trucks aren’t what they once were. Let’s step back first and take a closer look at Chrysler’s PT Cruiser, for example, which was awarded the distinguished Car of the Year award during this year’s competition by a 50-person jury. Its retro hot-rod styling made it a winner from the get-go, but its practicality and functionality — the marriage of sedan, minivan and SUV attributes — ensured that it was a shoo-in. Don’t forget, this “car” is categorized as a truck by the Feds, and its counterpart — the Acura MDX that drove away with Truck of the Year — is lauded for its carlike handling.

What’s new and upcoming to the highways, byways and four-car garages of our homeland? If Detroit’s annual show was any accurate depiction, you can forget the merger of automakers and remember the matrimony of segments. Light trucks (sport-utility vehicles, minivans and compact and full-sized trucks) are joining parts and hearts, creating unions between SUVs and trucks, minivans, sedans, wagons, and sports cars — and, in some cases, you can substitute “truck” for “SUV” and do the math again. If you thought Detroit’s carmakers, along with European and Asian manufacturers, were exhausted with variations of crossovers, hybrids or blends, it appears that they’ve only just begun

From the ASX — Mitsubishi’s aggressive, radical concept that blends sport-sedan handling and flexible SUV packaging dubbed the Active Sports Crossover — to the Model X (Honda’s sport wagon concept for young, active males with a moveable roof that retracts to create a pickup truck bed), many new concept designs are a fusion of form and function.

Once, each carmaker carved out its own brand image. And yet, what’s clear from this year’s show is that the image that many Americans want is perhaps less about “brand” and more about what trucks and SUVs embody in spirit and practicality: freedom, functionality and fun; active and adventuresome lifestyles; all with safety, security, fuel economy and environmentalism towed along for the ride.

Particularly noticeable on the runways and turntables this year is that along with the creative is the me-too syndrome: relying on others’ innovation to produce a company’s own quick response to a hot market trend or demographic.

The problem, however, is that today’s car culture is a moving target, and the modern truck and SUV buyer no longer fits a traditional demographic. There are young, middle-aged, older buyers; male and female buyers; upscale and low-income buyers; and buyers that like aggressive, king-of-the-road wheels to drive while others prefer more queenly styling for their stroll. The one thing held in common by today’s cars is the notion of being a rolling base camp, an extension of home and office and living room, set up with enough technology to launch a rocket ship or placate kids with endless hours of DVD-based entertainment.